import type { FormatDistanceFn, FormatDistanceLocale } from "../../../types.ts";

type FormatDistanceTokenValue =
  | string
  | {
      one: string;
      other: string;
      oneWithSuffix?: string;
      otherWithSuffix?: string;
    };

const formatDistanceLocale: FormatDistanceLocale<FormatDistanceTokenValue> = {
  lessThanXSeconds: {
    one: "1秒未満",
    other: "{{count}}秒未満",
    oneWithSuffix: "約1秒",
    otherWithSuffix: "約{{count}}秒",
  },

  xSeconds: {
    one: "1秒",
    other: "{{count}}秒",
  },

  halfAMinute: "30秒",

  lessThanXMinutes: {
    one: "1分未満",
    other: "{{count}}分未満",
    oneWithSuffix: "約1分",
    otherWithSuffix: "約{{count}}分",
  },

  xMinutes: {
    one: "1分",
    other: "{{count}}分",
  },

  aboutXHours: {
    one: "約1時間",
    other: "約{{count}}時間",
  },

  xHours: {
    one: "1時間",
    other: "{{count}}時間",
  },

  xDays: {
    one: "1日",
    other: "{{count}}日",
  },

  aboutXWeeks: {
    one: "約1週間",
    other: "約{{count}}週間",
  },

  xWeeks: {
    one: "1週間",
    other: "{{count}}週間",
  },

  aboutXMonths: {
    one: "約1か月",
    other: "約{{count}}か月",
  },

  xMonths: {
    one: "1か月",
    other: "{{count}}か月",
  },

  aboutXYears: {
    one: "約1年",
    other: "約{{count}}年",
  },

  xYears: {
    one: "1年",
    other: "{{count}}年",
  },

  overXYears: {
    one: "1年以上",
    other: "{{count}}年以上",
  },

  almostXYears: {
    one: "1年近く",
    other: "{{count}}年近く",
  },
};

export const formatDistance: FormatDistanceFn = (token, count, options) => {
  options = options || {};

  let result;

  const tokenValue = formatDistanceLocale[token];
  if (typeof tokenValue === "string") {
    result = tokenValue;
  } else if (count === 1) {
    if (options.addSuffix && tokenValue.oneWithSuffix) {
      result = tokenValue.oneWithSuffix;
    } else {
      result = tokenValue.one;
    }
  } else {
    if (options.addSuffix && tokenValue.otherWithSuffix) {
      result = tokenValue.otherWithSuffix.replace("{{count}}", String(count));
    } else {
      result = tokenValue.other.replace("{{count}}", String(count));
    }
  }

  if (options.addSuffix) {
    if (options.comparison && options.comparison > 0) {
      return result + "後";
    } else {
      return result + "前";
    }
  }

  return result;
};
